These are syringe maintenance kits for the Varispan™ Arm of JANUS® systems. They are available in a variety of volumes in units of 4 kits or 8 kits. The JANUS® Varispan™ systems are designed for multi-tipped processing regardless of the type of labware utilized in an assay. JANUS is able to automatically vary the spacing between sampling tips ensuring uncompromised throughput and flexibility. This makes the system versatile for accessing all kinds of labware such as tubes, vials, reagent reservoirs, and microplates. With an 8-channel system, the maximum spacing which can be reached between the individual tips is 40 mm. Varispan™ 4- or 8-tip arm provides independent motion and liquid level sensing in Z direction to access test tubes, microplates, deep well plates, and vials. Sampling probes offer variable spacing from 9 mm to 20 mm for 4-tip arm or 9 mm to 40 mm for 8-tip arm. Pipetting accuracy and precision of automated liquid handling systems is essential for data quality and integrity. JANUS® was specifically designed with pipetting performance in mind. WinPREP® is a flexible, powerful, and intuitive software application that controls the JANUS system. WinPREP® has the unique capability to adjust pipetting performance based upon liquid type, volume ranges, tip type, and dispense mode. WinPREP® software uses Performance Files, which contain optimized settings for various parameters that affect the variability of the volume transferred. These parameters include aspirate and dispense speeds, air gap sizes, waste and blowout volumes, and syringe delays. Performance files also include calibration parameters. A slope and offset can be obtained by linear regression analysis of dispense volumes in a specified range for a tip type. These allow you to optimize pipetting accuracy for your specific instrument and for specific liquids.